Add support for Shelly Dimmer 2 (#2954)

Co-authored-by: Niclas Larsson <niclas@edgesystems.se>
Co-authored-by: Jesse Hills <3060199+jesserockz@users.noreply.github.com>
Co-authored-by: Jernej Kos <jernej@kos.mx>
Co-authored-by: Richard Nauber <richard@nauber.dev>

tests/test1.yaml

@@ -1751,6 +1751,18 @@ light:
         to: 25
       - single_light_id: ${roomname}_lights
 
+  - platform: shelly_dimmer
+    name: "Shelly Dimmer Light"
+    power:
+      name: "Shelly Dimmer Power"
+    voltage:
+      name: "Shelly Dimmer Voltage"
+    current:
+      name: "Shelly Dimmer Current"
+    max_brightness: 500
+    firmware: "51.6"
+    uart_id: uart0
+
 remote_transmitter:
   - pin: 32
     carrier_duty_percent: 100%